Asthma is one of the most important underlying causes of morbidity and lost productivity in the US. Though more US adults with asthma have controller medicines, fewer than half of adults have their asthma controlled. To improve the quality of asthma care in the US it is essential for providers to continue to intensify treatments (e.g., adding additional controller medications), in keeping with the NAEPP Guidelines, until asthma symptoms are controlled, as well as to consistently apply other recommendations from evidence-based guidelines. Prompting patients to ask doctors for tests and treatments improves preventive care, but its effect on asthma management has not been studied. We have developed an interactive website to be used by patients with asthma between and before doctor visits. The program asks patients questions about their asthma symptoms and medications. Based on responses to these questions and decision rules, patients are given personalized feedback. The feedback includes questions that the patient should consider asking during their next doctor visit, along with a lay explanation of why they should ask each question and links to reputable websites (e.g., NHLBI) for further reading on each topic. As patients tend to get tests and treatments that they ask their physicians for, the website is designed to activate patients to ask questions that lead to better asthma care. The main aim of the study is to test the efficacy of providing access to the asthma module of the interactive website. We will randomize 408 adults with asthma, who are members of Highmark, to use the asthma (IC) or preventive services module of the website for 12 months. We hypothesize that, after 12 months of using the website, 70% of patients in the IC will have controlled asthma, compared to 55% of patients in the CC. Uncontrolled asthma is one of the greatest threats to the public's health and the productivity of the US workforce. As three in four Americans now have access to the Internet, interventions being tested such as this interactive website hold great promise for improving asthma care and for improving the public's health by improving the quality of care for other common, chronic illnesses. PUBLIC HEALTH RELEVANCE: This study will test the efficacy of a website to be used by patients with asthma between and before visits with their asthma care provider. Patients enter information about their symptoms and medications, which is combined with decision rules from evidence-based guidelines to provide patients with personalized feedback. The feedback is designed to help patients know what to ask during doctor visits, in order to better control their asthma.